Method for treating a patient undergoing chemotherapy

ABSTRACT

The present invention provides improved methods, kits, and pharmaceutical compositions for increasing hematopoietic cell survival and/or reducing or preventing the side effects of chemotherapy, and mobilizing hematopoietic progenitor cells from bone marrow into peripheral blood following chemotherapy, comprising administering an effective amount of angiotensinogen, angiotensin I (AI), AI analogues, AI fragments and analogues thereof, angiotensin II (AII), AII analogues, AII fragments or analogues thereof or AII AT 2  type 2 receptor agonists to a patient in need of chemotherapy.

CROSS REFERENCE

This application is a continuation of U.S. patent application Ser. No.10/842,877 filed May 10, 2004, now U.S. Pat. No. 7,338,938, which is acontinuation of U.S. application Ser. No. 09/723,197, filed Nov. 27,2000, now U.S. Pat. No. 6,762,167, which claims priority to U. S.Provisional Patent Application Nos: 60/201,470 filed May 3, 2000;60/220,804 filed Jul. 25, 2000; 60/233,375 filed Sept. 18, 2000;60/235,040 filed Sept. 25, 2000; and 60/243,955 filed Oct. 27, 2000, andwhich is a Continuation-In-Part of U.S. patent application Ser. No.09/307,940 filed May 10, 1999, now U.S. Pat. No. 6,475,988.

FIELD OF THE INVENTION

The present invention relates to methods, pharmaceutical compositions,and articles of manufacture for treating a patient undergoingchemotherapy, particularly for increasing hematopoietic cell survivaland stem cell mobilization, and reducing the incidence and/or severityof chemotherapy-related side effects.

BACKGROUND OF THE INVENTION

People diagnosed as having cancer are frequently treated with single ormultiple cytotoxic chemotherapeutic agents (cytotoxic agents) to killcancer cells at the primary tumor site or at distant sites to wherecancer has metastasized. (U.S. Pat. No. 5,605,931 incorporated byreference herein in its entirety.) Chemotherapy treatment is giveneither in a single or in several large doses or, more commonly, it isgiven in small doses 1 to 4 times a day over variable times of weeks tomonths. There are many cytotoxic agents used to treat cancer, and theirmechanisms of action are generally poorly understood.

Irrespective of the mechanism, useful chemotherapeutic agents are knownto injure and kill cells of both tumors and normal tissues. Thesuccessful use of chemotherapeutic agents to treat cancer depends uponthe differential killing effect of the agent on cancer cells compared toits side effects on critical normal tissues. Among these effects are thekilling of hematopoietic blood forming cells, and the killing andsuppression of the white blood cells, which can lead to infection. Acuteand chronic bone marrow toxicities are also major limiting factors inthe treatment of cancer. They are both related to a decrease in thenumber of hemopoietic cells (e.g., pluripotent stem cells and otherprogenitor cells) caused by both a lethal effect of cytotoxic agents orradiation on these cells, and via differentiation of stem cells provokedby a feed-back mechanism induced by the depletion of more mature marrowcompartments. (U.S. Pat. No. 5,595,973 incorporated by reference hereinin its entirety.) Stimulators and inhibitors of bone marrow kineticsplay a prominent role in the induction of damage and recovery patterns(Tubiana, M., et al., Radiotherapy and Oncology 29:1, 1993).

Prevention of, or protection from, the side effects of chemotherapywould be a great benefit to cancer patients. The many previous effortsto reduce these side effects have been largely unsuccessful. Forlife-threatening side effects, efforts have concentrated on altering thedose and schedules of the chemotherapeutic agent to reduce the sideeffects. Other options are becoming available, such as the use ofgranulocyte colony stimulating factor (G-CSF),granulocyte-macrophage-CSF (GM-CSF), epidermal growth factor (EGF),interleukin 11, erythropoietin, thrombopoietin, megakaryocytedevelopment and growth factor, pixykines, stem cell factor, FLT-ligand,as well as interleukins 1, 3, 6, and 7, to increase the number of normalcells in various tissues before the start of chemotherapy (See Jimenezand Yunis, Cancer Research 52:413-415; 1992). The mechanisms ofprotection by these factors, while not fully understood, are most likelyassociated with an increase in the number of normal critical targetcells before treatment with cytotoxic agents, and not with increasedsurvival of cells following chemotherapy.

Acute myelosuppression as a consequence of cytotoxic chemotherapy iswell recognized as a dose-limiting factor in cancer treatment. (U.S.Pat. No. 5,595,973) Although other normal tissues may be adverselyaffected, bone marrow is particularly sensitive to theproliferation-specific treatment such as chemotherapy or radiotherapy.For some cancer patients, hematopoietic toxicity frequently limits theopportunity for chemotherapy dose escalation. Repeated or high dosecycles of chemotherapy may be responsible for severe stem cell depletionleading to serious long-term hematopoietic sequelea and marrowexhaustion.

Despite advances in the field of chemotherapy, prior art methods haveproven to be of limited utility in minimizing chemotherapy-induceddepletion of hematopoietic stem cells and their progeny. Thus, there isa need for improved therapeutic methods and pharmaceutical compositionsfor increasing hematopoietic cell survival following chemotherapeutictreatments, as well as for decreasing the adverse effects ofchemotherapy on the bone marrow.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides methods, pharmaceuticalcompositions, and articles of manufacture for treating a patientundergoing chemotherapy, for increasing hematopoietic cell survivalfollowing chemotherapy, for reducing or preventing other side effects ofchemotherapy, such as anemia, and for mobilizing hematopoieticprogenitor cells from bone marrow into peripheral blood, comprisingadministering an amount effective for such purposes of angiotensinogen,angiotensin I (AI), AI analogues, AI fragments and analogues thereof,angiotensin II (AII), AII analogues, AII fragments or analogues thereof,AII AT₂ type 2 receptor agonists, or ACE inhibitors.

These aspects and other aspects of the invention become apparent inlight of the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph showing the effect of AII treatment on white bloodcell number in the blood 7 days after 5FU treatment.

FIG. 2 is a graph showing the effect of AII treatment on white bloodcell number in the spleen 7 days after 5FU treatment.

FIG. 3 is a graph showing the effect of AII treatment on white bloodcell number in the thymus 7 days after 5FU treatment.

FIG. 4 is a graph showing the effect of AII treatment on white bloodcell number in the bone marrow 7 days after 5FU treatment.

FIG. 5 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following blood harvest 7 daysafter 5FU treatment.

FIG. 6 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following spleen harvest 7 daysafter 5FU treatment.

FIG. 7 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following bone marrow harvest 7days after 5FU treatment.

FIG. 8 is a graph showing the effect of AII treatment on CFU-GM cellnumber in the blood on day 7 after 5FU treatment.

FIG. 9 is a graph showing the effect of AII treatment on white bloodcell number in the spleen on day 14 after 5FU treatment.

FIG. 10 is a graph showing the effect of AII treatment on white bloodcell number in the thymus on day 14 after 5FU treatment.

FIG. 11 is a graph showing the effect of AII treatment on white bloodcell number in the bone marrow on day 14 after 5FU treatment.

FIG. 12 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following spleen harvest 14days after 5FU treatment.

FIG. 13 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following blood harvest 14 daysafter 5FU treatment.

FIG. 14 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following blood harvest 14 daysafter 5FU treatment.

FIG. 15 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following spleen harvest 14days after 5FU treatment.

FIG. 16 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following bone marrow harvest 7days after 5FU treatment.

FIG. 17 is a graph showing the effect of AII treatment on CFU-GM cellnumber on day 7 after culture initiation following femur harvest 7 daysafter 5FU treatment.

FIG. 18 is a graph showing the effect of AII treatment on CFU-GM cellnumber in the bone marrow on day 7 after 5FU treatment.

FIG. 19 is a graph showing the effect of AII treatment on CFU-GM cellnumber in the spleen on day 7 after 5FU treatment.

FIG. 20 is a graph showing the effect of AII treatment on white bloodcell number in the blood on day 14 after 5FU treatment.

FIG. 21 is a graph of a different experiment showing the effect of AIItreatment on white blood cell number in the blood on days 4, 7, and 10after 5FU treatment.

FIG. 22 is a graph showing the effect of AII(1-7) treatment on whiteblood cell number in the blood on day 14 after 5FU treatment.

FIG. 23 is a graph showing the effect of 1GD treatment on white bloodcell number in the blood on day 14 after 5FU treatment.

FIG. 24 is a graph showing the effect of 2GD treatment on white bloodcell number in the blood on day 14 after 5FU treatment.

FIG. 25 is a graph showing the effect of 5GD treatment on white bloodcell number in the blood on day 14 after 5FU treatment.

FIG. 26 is a graph showing the effect of 9GD treatment on white bloodcell number in the blood on day 14 after 5FU treatment.

FIG. 27 is a graph showing the effect of 10 μg AII and AII analogues andfragments on GM-CFU numbers in the bone marrow on day 10 after 5FUtreatment.

FIG. 28 is a graph showing the effect of 100 μg AII and AII analoguesand fragments on GM-CFU numbers in the bone marrow on day 10 after 5FUtreatment.

FIG. 29 is a graph showing the effect of 10 μg AII and AII analogues andfragments on GM-CFU numbers in the blood on day 10 after 5FU treatment.

FIG. 30 is a graph showing the effect of 100 μg AII and AII analoguesand fragments on GM-CFU numbers in the blood on day 10 after 5FUtreatment.

FIGS. 31 a and b. Female C57B1/6 mice, 6-8 weeks old, were treated with200 mg/kg cytoxan by intravenous injection. Two days after (panel a) andtwo days before (panel b) cytoxan injection, subcutaneous administrationof AII(1-7) was initiated. Various times after cytoxan injection, theanimals were necropsied and peripheral blood harvested. The number ofwhite blood cells was counted by hematocytometer after red blood celllysis. An asterisk indicates a result significantly different fromsaline control (p≦0.05). These data are mean and standard error of 4animals per group (dose and time point).

FIGS. 32 a and b. Female C57B1/6 mice, 6-8 weeks old, were treated with200 mg/kg cytoxan by intravenous injection. Two days after and two daysbefore cytoxan injection, subcutaneous administration of AII(1-7) wasinitiated. Twenty eight after cytoxan injection, the animals werenecropsied and bone marrow (panel a) or peripheral blood (panel b)harvested. The number of GM-CFU formed from cells isolated from bonemarrow or peripheral blood after red blood cell lysis by culturing insemi solid medium containing recombinant colony stimulating factors wascounted. An asterisk indicates a result significantly different fromsaline control (p≦0.05). These data are mean and standard error of 3animals per group (dose and time point).

FIG. 33. Effect of AII analogues and enalapril on the increase in whiteblood cells in the peripheral blood after intravenous administration of5FU.

FIG. 34. Effect of AII analogues and enalapril on the increase in whiteblood cells in the peripheral blood after intravenous administration of5FU.

FIG. 35. Effect of AII analogues and enalapril on the increase in whiteblood cells in the peripheral blood after intravenous administration of5FU.

FIG. 36. Effect of AII analogues and enalapril on platelet increaseafter intravenous administration of 5FU.

FIG. 37. Effect of AII analogues and enalapril on platelet increaseafter intravenous administration of 5FU.

FIG. 38. Effect of AII analogues and enalapril on platelet increaseafter intravenous administration of 5FU.

FIG. 39. Effect of AII analogues and enalapril on hemoglobin increaseafter intravenous administration of 5FU.

FIG. 40. Effect of AII analogues and enalapril on hemoglobin increaseafter intravenous administration of 5FU.

FIG. 41. Effect of AII analogues and enalapril on hemoglobin increaseafter intravenous administration of 5FU.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Within this application, unless otherwise stated, the techniquesutilized may be found in any of several well-known references such as:Molecular Cloning: A Laboratory Manual (Sambrook, et al., 1989, ColdSpring Harbor Laboratory Press), Gene Expression Technology (Methods inEnzymology, Vol. 185, edited by D. Goeddel, 1991. Academic Press, SanDiego, Calif.), “Guide to Protein Purification” in Methods in Enzymology(M. P. Deutshcer, ed., (1990) Academic Press, Inc.); PCR Protocols: AGuide to Methods and Applications (Innis, et al. 1990. Academic Press,San Diego, Calif.), Culture of Animal Cells: A Manual of BasicTechnique, 2^(nd) Ed. (R. I. Freshney. 1987. Liss, Inc. New York, N.Y.),Gene Transfer and Expression Protocols, pp. 109-128, ed. E. J. Murray,The Humana Press Inc., Clifton, N.J.), and the Ambion 1998 Catalog(Ambion, Austin, Tex.).

As defined herein the phrase “hematopoietic cells” refers toundifferentiated hematopoietic stem cells, to committed hematopoieticprogenitor cells, and to differentiated hematopoietic cells including,but not limited to megakaryocytes, platelets, red blood cells,monocytes, neutrophils, macrophages, and lymphocytes.

As defined herein, “chemotherapy side effects” encompass any deleteriouseffects suffered as a result of chemotherapy, including but not limitedto hematopoietic toxicity, decreased mobilization of hematopoieticprogenitor cells from bone marrow into the peripheral blood; anemia,myelosuppression, pancytopenia, thrombocytopenia, neutropenia,lymphopenia, leukopenia, stomatitis, alopecia, headache, and musclepain.

Unless otherwise indicated, the term “angiotensin converting enzymeinhibitors” or “ACE inhibitors” includes any compound that inhibits theconversion of the decapeptide angiotensin I to angiotensin II, andinclude but are not limited to alacepril, alatriopril, altioprilcalcium, ancovenin, benazepril, benazepril hydrochloride, benazeprilat,benzazepril, benzoylcaptopril, captopril, captopril-cysteine,captopril-glutathione, ceranapril, ceranopril, ceronapril, cilazapril,cilazaprilat, converstatin, delapril, delapril-diacid, enalapril,enalaprilat, enalkiren, enapril, epicaptopril, foroxymithine,fosfenopril, fosenopril, fosenopril sodium, fosinopril, fosinoprilsodium, fosinoprilat, fosinoprilic acid, glycopril, hemorphin-4,idapril, imidapril, indolapril, indolaprilat, libenzapril, lisinopril,lyciumin A, lyciumin B, mixanpril, moexipril, moexiprilat, moveltipril,muracein A, muracein B, muracein C, pentopril, perindopril,perindoprilat, pivalopril, pivopril, quinapril, quinapril hydrochloride,quinaprilat, ramipril, ramiprilat, spirapril, spirapril hydrochloride,spiraprilat, spiropril, spiropril hydrochloride, temocapril, temocaprilhydrochloride, teprotide, trandolapril, trandolaprilat, utibapril,zabicipril, zabiciprilat, zofenopril and zofenoprilat. (See for exampleJackson, et al., Renin and Angiotensin in Goodman & Gilman's ThePharmacological Basis of Therapeutics, 9th ed., eds. Hardman, et al.(McGraw Hill, 1996); and U.S. Pat. No. 5,977,159.)

U.S. Pat. No. 5,015,629 to DiZerega (the entire disclosure of which ishereby incorporated by reference) describes a method for increasing therate of healing of wound tissue, comprising the application to suchtissue of angiotensin II (AII) in an amount that is sufficient for saidincrease. The application of AII to wound tissue significantly increasesthe rate of wound healing, leading to a more rapid re-epithelializationand tissue repair. The term AII refers to an octapeptide present inhumans and other species having the sequenceAsp-Arg-Val-Tyr-Ile-His-Pro-Phe [SEQ ID NO:1]. The biological formationof angiotensin is initiated by the action of renin on the plasmasubstrate angiotensinogen (Clouston et al., Genomics 2:240-248 (1988);Kageyama et al, Biochemistry 23:3603-3609; Ohkubo et al., Proc. Natl.Acad. Sci. 80:2196-2200 (1983); each reference hereby incorporated inits entirety). The substance so formed is a decapeptide calledangiotensin I (AI) which is converted to AII by the angiotensinconverting enzyme (ACE) which removes the C-terminal His-Leu residuesfrom AI [SEQ ID NO: 37]. AII is a known pressor agent and iscommercially available.

Studies have shown that AII increases mitogenesis and chemotaxis incultured cells that are involved in wound repair, and also increasestheir release of growth factors and extracellular matrices (diZerega,U.S. Pat. No. 5,015,629; Dzau et. al., J. Mol. Cell. Cardiol. 21:S7(Supp III) 1989; Berk et. al., Hypertension 13:305-14 (1989); Kawahara,et al., BBRC 150:52-9 (1988); Naftilan, et al., J. Clin. Invest.83:1419-23 (1989); Taubman et al., J. Biol. Chem. 264:526-530 (1989);Nakahara, et al., BBRC 184:811-8 (1992); Stouffer and Owens, Circ. Res.70:820 (1992); Wolf, et al., Am. J. Pathol. 140:95-107 (1992); Bell andMadri, Am. J. Pathol. 137:7-12 (1990). In addition, AII was shown to beangiogenic in rabbit corneal eye and chick chorioallantoic membranemodels (Fernandez, et al., J. Lab. Clin. Med. 105:141 (1985); LeNoble,et al., Eur. J. Pharmacol. 195:305-6 (1991).

We have previously demonstrated that angiotensinogen, angiotensin I(AI), AI analogues, AI fragments and analogues thereof, angiotensin II(AII), AII analogues, AII fragments or analogues thereof, and AII AT₂type 2 receptor agonists are effective in accelerating wound healing andthe proliferation of certain cell types, such as hematopoietic stem andlineage specific cells. See, for example, co-pending U.S. patentapplication Ser. No. 09/012,400, filed Jan. 23, 1998; 09/198,806 filedNov. 24, 1998; 09/264,563, filed Mar. 8, 2000; 09/287,674, filed Apr. 7,1999; 09/255,136 filed Feb. 19, 1999; 09/245,680, filed Feb. 8, 1999;09/250,703 filed Feb. 15, 1999; 09/246,525 filed Feb. 8, 1999;09/266,293 Mar. 11, 1999; 09/332,582 filed Jun. 14, 1999; 09/373,962filed Aug. 13, 1999; and 09/352,191 filed Jul. 12, 1999; as well as U.S.Pat. Ser. Nos. 5,015,629; 5,629,292; 5,716,935; 5,834,432; and5,955,430; 6,096,709; 6,110,895.

Angiotensin II and its sarcosine analogue have also been used incombination with cytotoxic drugs to induce hypertension in humans andexperimental animals undergoing intra-arterial and intraperitonealchemotherapy. (Taniguchi et al., J. Nuclear Medicine 37:1522-1523(1996); Morita et al., Am. J. Clin. Oncol. 15:188-193 (1992); Ohigashiet al., Hepato-Gastroenterology 43:338-345 (1996); Cancer Chemother.Pharmacol. 39:113-121 (1996); Kuroiwa et al., Cancer Chemother.Pharmacol. 35:357-363 (1995); Li et al., Br. J. Cancer 67:975-980(1993); Dworkin et al., Br. J. Cancer 76:1205-1210 (1997); Sato et al.,World J. Surg. 19:836-842 (1995); Mutoh et al., Urol. Int. 48:175-180(1992). In each of these cases, the use of angiotensin II was intendedto selectively increase blood flow to the tumor vasculature relative tonormal vasculature, thereby increasing the delivery of cytotoxic agentto the tumor. None of these studies demonstrated or suggested that theuse of angiotensin II or its sarcosine analogue would be effective inincreasing hematopoietic cell survival, hematopoietic stem cellmobilization into peripheral blood following chemotherapy, or thereduction in chemotherapy side effects.

Based on all of the above, it would be unexpected that the use ofangiotensinogen, angiotensin I (AI), AI analogues, AI fragments andanalogues thereof, AII, AII analogues, AII fragments or analoguesthereof, AII AT₂ type 2 receptor agonists, or ACE inhibitors would beeffective in increasing hematopoietic cell survival followingchemotherapy, for reducing or preventing other side effects ofchemotherapy, such as anemia, and for mobilizing hematopoieticprogenitor cells from bone marrow into peripheral blood.

A peptide agonist selective for the AT2 receptor (AII has 100 timeshigher affinity for AT2 than AT1) has been identified. This peptide isp-aminophenylalanine 6-AII [“(p-NH₂-Phe)-6-AII)”],Asp-Arg-Val-Tyr-Ile-Xaa-Pro-Phe [SEQ ID NO. 36] wherein Xaa is p-NH₂-Phe(Speth and Kim, BBRC 169:997-1006 (1990). This peptide gave bindingcharacteristics comparable to AT2 antagonists in the experimental modelstested (Catalioto, et al., Eur. J. Pharmacol. 256:93-97 (1994); Bryson,et al., Eur. J. Pharmacol. 225:119-127 (1992).

The effects of AII receptor and AII receptor antagonists have beenexamined in two experimental models of vascular injury and repair whichsuggest that both AII receptor subtypes (AT1 and AT2) play a role inwound healing (Janiak et al., Hypertension 20:737-45 (1992); Prescott,et al., Am. J. Pathol. 139:1291-1296 (1991); Kauffman, et al., Life Sci.49:223-228 (1991); Viswanathan, et al., Peptides 13:783-786 (1992);Kimura, et al., BBRC 187:1083-1090 (1992).

Many studies have focused upon AII(1-7) (AII residues 1-7) or otherfragments of AII to evaluate their activity. AII(1-7) elicits some, butnot the full range of effects elicited by AII. Pfeilschifter, et al.,Eur. J. Pharmacol. 225:57-62 (1992); Jaiswal, et al., Hypertension19(Supp. II):II-49-II-55 (1992); Edwards and Stack, J. Pharmacol. Exper.Ther. 266:506-510 (1993); Jaiswal, et al., J. Pharmacol. Exper. Ther.265:664-673 (1991); Jaiswal, et al., Hypertension 17:1115-1120 (1991);Portsi, et al., Br. J. Pharmacol. 111:652-654 (1994).

Other data suggests that the AII fragment AII(1-7) acts through areceptor(s) that is distinct from the AT1 and AT2 receptors whichmodulate AII activity. (Ferrario et al., J. Am. Soc. Nephrol.9:1716-1722 (1998); Iyer et al., Hypertension 31:699-705 (1998); Freemanet al., Hypertension 28:104 (1996); Ambuhl et al., Brain Res. Bull.35:289 (1994)). Thus, AII(1-7) activity on a particular cell type cannotbe predicted based solely on the effect of AII on the same cell type. Infact, there is some evidence that AII(1-7) often opposes the actions ofAII. (See, for example, Ferrario et al., Hypertension 30:535-541 (1997))

As hereinafter defined, a preferred class of AT2 agonists for use inaccordance with the present invention comprises angiotensinogen,angiotensin I (AI), AI analogues, AI fragments and analogues thereof,AII, AII analogues, AII fragments or analogues thereof or AII AT₂ type 2receptor agonists having p-NH-Phe in a position corresponding to aposition 6 of AII. In addition to peptide agents, various nonpeptidicagents (e.g., peptidomimetics) having the requisite AT2 agonist activityare further contemplated for use in accordance with the presentinvention, as well as compounds fused to the active agent to providesome further desired property.

The active AII analogues, fragments of AII and analogues thereof ofparticular interest in accordance with the present invention comprise asequence of at least three contiguous amino acids of groups R¹-R⁸ in thesequence of general formula IR¹-R²-R³-R⁴-R⁵-R⁶-R⁷⁻R⁸

-   -   wherein R¹ is selected from Asp, Glu, Asn, Acpc        (1-aminocyclopentane carboxylic acid), Ala, Me²Gly, Pro, Bet,        Glu(NH₂), Gly, Asp(NH₂) and Suc,    -   R² is selected from Arg, Lys, Ala, Orn, Ser(Ac), Sar, D-Arg and        D-Lys;    -   R³ is selected from the group consisting of Val, Ala, Leu, Lys,        norLeu, Ile, Gly, Pro, Aib, Acpc and Tyr;    -   R⁴ is selected from the group consisting of Tyr, Tyr(PO₃)₂, Thr,        Ser, Ala, homoSer and azaTyr;    -   R⁵ is selected from the group consisting of Ile, Ala, Leu,        norLeu, Val and Gly;    -   R⁶ is selected from the group consisting of His, Arg or        6-NH₂-Phe;    -   R⁷ is selected from the group consisting of Pro or Ala; and    -   R⁸ is selected from the group consisting of Phe, Phe(Br), Ile        and Tyr, excluding sequences including R⁴ as a terminal Tyr        group.

Particularly preferred combinations for R¹ and R² are Asp-Arg, Asp-Lys,Glu-Arg and Glu-Lys.

In alternate embodiments, the active agents comprise a sequence of atleast four, five, six, seven, or eight contiguous amino acids of groupsR¹-R⁸ in the sequence of general formula I. In a further alternative,the active agents consist essentially of a sequence of at least four,five, six, seven, or eight contiguous amino acids of groups R¹-R⁸ in thesequence of general formula I.

Compounds falling within the category of AT2 agonists useful in thepractice of the invention include the All analogues set forth abovesubject to the restriction that R⁶ is p-NH₂-Phe. In a further preferredembodiment of all of the aspects of the invention, the active agentcomprises a sequence selected from the group consisting ofangiotensinogen, SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:9, SEQ IDNO:10, SEQ ID NO:11, SEQ ID NO:12, SEQ ID NO:13, SEQ ID NO:16, SEQ IDNO:17, SEQ ID NO:18, SEQ ID NO:19, SEQ ID NO:20, SEQ ID NO:21, SEQ IDNO:22, SEQ ID NO:23, SEQ ID NO:24, SEQ ID NO:25, SEQ ID NO:26, SEQ IDNO:27, SEQ ID NO:28, SEQ ID NO:29, SEQ ID NO:30, SEQ ID NO:31, SEQ IDNO: 32, SEQ ID NO:33, SEQ ID NO: 34; SEQ ID NO:35, SEQ ID NO:36, SEQ IDNO:37, SEQ ID NO:38, SEQ ID NO:39, SEQ ID NO:40, and SEQ ID NO:41 .

Particularly preferred embodiments of this class comprise the followingsequences: AII (SEQ ID NO:1), AIII or AII(2-8),Arg-Val-Tyr-Ile-His-Pro-Phe [SEQ ID NO:2]; AII(3-8), also known asdes1-AIII or AIV, Val-Tyr-Ile-His-Pro-Phe [SEQ ID NO:3]; AII(1-7),Asp-Arg-Val-Tyr-Ile-His-Pro {SEQ ID NO:4]; AII(2-7).Arg-Val-Tyr-Ile-His-Pro [SEQ ID NO:5]; AII(3-7), Val-Tyr-Ile-His-Pro[SEQ ID NO:6]; AII(5-8), Ile-His-Pro-Phe [SEQ ID NO:7]; AII(1-6),Asp-Arg-Val-Tyr-Ile-His [SEQ ID NO:8]; AII(1-5), Asp-Arg-Val-Tyr-Ile[SEQ ID NO:9]; AII(1-4), Asp-Arg-Val-Tyr [SEQ ID NO:10]; and AII(1-3),Asp-Arg-Val [SEQ ID NO:11]. Other preferred embodiments include:Arg-norLeu-Tyr-Ile-His-Pro-Phe [SEQ ID NO:12] andArg-Val-Tyr-norLeu-His-Pro-Phe [SEQ ID NO:13]. Still another preferredembodiment encompassed within the scope of the invention is a peptidehaving the sequence Asp-Arg-Pro-Tyr-Ile-His-Pro-Phe [SEQ ID NO:31].AII(6-8), His-Pro-Phe [SEQ ID NO:14] and AII(4-8), Tyr-Ile-His-Pro-Phe[SEQ ID NO:15] were also tested and found not to be effective.

In a particularly preferred embodiment, the active agents of the presentinvention comprise an amino acid sequence of the following generalformula:

Asp-Arg-R1-R2-Ile-His-Pro-R³, wherein

R1 is selected from the group consisting of Val, Pro, Lys, Norleu, andLeu;

R2 is selected from the group consisting of Ala, Tyr, and Tyr(PO₃)₂; and

R3 is Phe or is absent.

In a most particularly preferred embodiment, the active agent comprisesa sequence selected from the group consisting of SEQ ID NO:1, SEQ IDNO:4, SEQ ID NO:31, SEQ ID NO:32, SEQ ID NO:33, SEQ ID NO:38, SEQ IDNO:39, SEQ ID NO:40, and SEQ ID NO:41.

Another class of compounds of particular interest in accordance with thepresent invention are those comprising a sequence of the general formulaIIR²-R³-R⁴-R⁵-R⁶-R⁷-R⁸

-   -   in which R² is selected from the group consisting of H, Arg,        Lys, Ala, Orn, Ser(Ac), Sar, D-Arg and D-Lys;    -   R³ is selected from the group consisting of Val, Ala, Leu,        norLeu, Lys, Ile, Gly, Pro, Aib, Acpc and Tyr;    -   R⁴ is selected from the group consisting of Tyr, Tyr(PO₃)₂, Thr,        Ser, Ala homoSer and azaTyr;    -   R⁵ is selected from the group consisting of Ile, Ala, Leu,        norLeu, Val and Gly;    -   R⁶ is selected from the group consisting of His, Arg or        6-NH₂-Phe;    -   R⁷ is selected from the group consisting of Pro or Ala; and    -   R⁸ is selected from the group consisting of Phe, Phe(Br), Ile        and Tyr.

A particularly preferred subclass of the compounds of general formula IIhas the formula

R²-R³-Tyr-R⁵-His-Pro-Phe [SEQ ID NO: 16]

wherein R², R³ and R⁵ are as previously defined. Particularly preferredis angiotensin III of the formula Arg-Val-Tyr-Ile-His-Pro-Phe [SEQ IDNO:2]. Other preferred compounds include peptides having the structuresArg-Val-Tyr-Gly-His-Pro-Phe [SEQ ID NO:17] andArg-Val-Tyr-Ala-His-Pro-Phe [SEQ ID NO:18]. The fragment AII(4-8) wasineffective in repeated tests; this is believed to be due to the exposedtyrosine on the N-terminus.

In the above formulas, the standard three-letter abbreviations for aminoacid residues are employed. In the absence of an indication to thecontrary, the L-form of the amino acid is intended. Other residues areabbreviated as follows:

TABLE 1 Abbreviation for Amino Acids Me²Gly N,N-dimethylglycyl Bet1-carboxy-N,N,N-trimethylmethanaminium hydroxide inner salt (betaine)Suc Succinyl Phe(Br) p-bromo-L-phenylalanyl azaTyr aza-α′-homo-L-tyrosylAcpc 1-aminocyclopentane carboxylic acid Aib 2-aminoisobutyric acid SarN-methylglycyl (sarcosine)

It has been suggested that AII and its analogues adopt either a gamma ora beta turn (Regoli, et al., Pharmacological Reviews 26:69 (1974)). Ingeneral, it is believed that neutral side chains in position R³, R⁵ andR⁷ may be involved in maintaining the appropriate distance betweenactive groups in positions R⁴, R⁶ and R⁸ primarily responsible forbinding to receptors and/or intrinsic activity. Hydrophobic side chainsin positions R³, R⁵ and R⁸ may also play an important role in the wholeconformation of the peptide and/or contribute to the formation of ahypothetical hydrophobic pocket.

Appropriate side chains on the amino acid in position R² may contributeto affinity of the compounds for target receptors and/or play animportant role in the conformation of the peptide. For this reason, Argand Lys are particularly preferred as R².

For purposes of the present invention, it is believed that R³ may beinvolved in the formation of linear or nonlinear hydrogen bonds with R⁵(in the gamma turn model) or R⁶ (in the beta turn model). R³ would alsoparticipate in the first turn in a beta antiparallel structure (whichhas also been proposed as a possible structure). In contrast to otherpositions in general formula I, it appears that beta and gamma branchingare equally effective in this position. Moreover, a single hydrogen bondmay be sufficient to maintain a relatively stable conformation.Accordingly, R³ may suitably be selected from Val, Ala, Leu, norLeu,Ile, Gly, Pro, Aib, Acpc and Tyr. Lys has also been found to beeffective at position R³.

With respect to R⁴, conformational analyses have suggested that the sidechain in this position (as well as in R³ and R⁵) contribute to ahydrophobic cluster believed to be essential for occupation andstimulation of receptors. Thus, R⁴ is preferably selected from Tyr, Thr,Tyr (PO₃)₂, homoSer, Ser and azaTyr. In this position, Tyr isparticularly preferred as it may form a hydrogen bond with the receptorsite capable of accepting a hydrogen from the phenolic hydroxyl (Regoli,et al. (1974), supra). Ala has also been found to be effective atposition R⁴.

In position R⁵, an amino acid with a β aliphatic or alicyclic chain isparticularly desirable. Therefore, while Gly is suitable in position R⁵,it is preferred that the amino acid in this position be selected fromIle, Ala, Leu, norLeu, Gly and Val.

In the angiotensinogen, AI, AI analogues, AI fragments and analoguesthereof, AII analogues, fragments and analogues of fragments ofparticular interest in accordance with the present invention, R⁶ is His,Arg or 6-NH₂-Phe. The unique properties of the imidazole ring ofhistidine (e.g., ionization at physiological pH, ability to act asproton donor or acceptor, aromatic character) are believed to contributeto its particular utility as R⁶. For example, conformational modelssuggest that His may participate in hydrogen bond formation (in the betamodel) or in the second turn of the antiparallel structure byinfluencing the orientation of R⁷. Similarly, it is presently consideredthat R⁷ should be Pro in order to provide the most desirable orientationof R⁸. In position R⁸, both a hydrophobic ring and an anionic carboxylterminal appear to be particularly useful in binding of the analogues ofinterest to receptors; therefore, Tyr and especially Phe are preferredfor purposes of the present invention.

Analogues of particular interest include the following:

TABLE 2 Angiotensin II Analogues All Analogue Sequence Name Amino AcidSequence Identifier Analogue 1 Asp-Arg-Val-Tyr-Val-His- SEQ ID NO: 19Pro-Phe Analogue 2 Asn-Arg-Val-Tyr-Val-His- SEQ ID NO: 20 Pro-PheAnalogue 3 Ala-Pro-Gly-Asp-Arg-Ile- SEQ ID NO: 21 Tyr-Val-His-Pro-PheAnalogue 4 Glu-Arg-Val-Tyr-Ile-His- SEQ ID NO: 22 Pro-Phe Analogue 5Asp-Lys-Val-Tyr-Ile-His- SEQ ID NO: 23 Pro-Phe Analogue 6Asp-Arg-Ala-Tyr-Ile-His- SEQ ID NO: 24 Pro-Phe Analogue 7Asp-Arg-Val-Thr-Ile-His- SEQ ID NO: 25 Pro-Phe Analogue 8Asp-Arg-Val-Tyr-Leu-His- SEQ ID NO: 26 Pro-Phe Analogue 9Asp-Arg-Val-Tyr-Ile-Arg- SEQ ID NO: 27 Pro-Phe Analogue 10Asp-Arg-Val-Tyr-Ile-His- SEQ ID NO: 28 Ala-Phe Analogue 11Asp-Arg-Val-Tyr-Ile-His- SEQ ID NO: 29 Pro-Tyr Analogue 12Pro-Arg-Val-Tyr-Ile-His- SEQ ID NO: 30 Pro-Phe Analogue 13Asp-Arg-Pro-Tyr-Ile-His- SEQ ID NO: 31 Pro-Phe Analogue 14Asp-Arg-Val-Tyr(PO₃)₂-Ile- SEQ ID NO: 32 His-Pro-Phe Analogue 15Asp-Arg-norLeu-Tyr-Ile- SEQ ID NO: 33 His-Pro-Phe Analogue 16Asp-Arg-Val-Tyr-norLeu- SEQ ID NO: 34 His-Pro-Phe Analogue 17Asp-Arg-Val-homoSer-Tyr- SEQ ID NO: 35 Ile-His-Pro-Phe

The polypeptides of the instant invention may be produced by anystandard method, including but not limited to recombinant DNA technologyand conventional synthetic methods including, but not limited to, thoseset forth in J. M. Stewart and J. D. Young, Solid Phase PeptideSynthesis, 2nd ed., Pierce Chemical Co., Rockford, Ill. (1984) and J.Meienhofer, Hormonal Proteins and Peptides, Vol. 2, Academic Press, NewYork, (1973) for solid phase synthesis and E. Schroder and K. Lubke, ThePeptides, Vol. 1, Academic Press, New York, (1965) for solutionsynthesis. The disclosures of the foregoing treatises are incorporatedby reference herein.

In general, these methods involve the sequential addition of protectedamino acids to a growing peptide chain (U.S. Pat. No. 5,693,616, hereinincorporated by reference in its entirety). Normally, either the aminoor carboxyl group of the first amino acid and any reactive side chaingroup are protected. This protected amino acid is then either attachedto an inert solid support, or utilized in solution, and the next aminoacid in the sequence, also suitably protected, is added under conditionsamenable to formation of the amide linkage. After all the desired aminoacids have been linked in the proper sequence, protecting groups and anysolid support are removed to afford the crude polypeptide. Thepolypeptide is desalted and purified, preferably chromatographically, toyield the final product.

Preferably, peptides are synthesized according to standard solid-phasemethodologies, such as may be performed on an Applied Biosystems Model430A peptide synthesizer (Applied Biosystems, Foster City, Calif.),according to manufacturer's instructions. Other methods of synthesizingpeptides or peptidomimetics, either by solid phase methodologies or inliquid phase, are well known to those skilled in the art. Alternatively,the active agents can be prepared by standard recombinant DNAtechniques.

In one aspect, the present invention provides methods and kits forincreasing hematopoietic cell survival following chemotherapy, andtreating and preventing the adverse effects of chemotherapy, comprisingthe administration of angiotensinogen, angiotensin I (AI), AI analogues,AI fragments and analogues thereof, angiotensin II (AII), AII analogues,AII fragments or analogues thereof or AII AT₂ type 2 receptor agonists(hereinafter referred to as “active agents”) to a patient undergoingchemotherapy.

In another aspect, the present invention provides methods and kits formobilizing hematopoietic progenitor cells from bone marrow intoperipheral blood comprising the administration of the active agents ofthe invention to a patient in need of such treatment. This aspect of theinvention can also be used to treat a patient in need of chemotherapy.

The methods of the invention are appropriate for use with chemotherapyusing any cytotoxic agent, including, but not limited to,cyclophosphamide, taxol, 5-fluorouracil, adriamycin, cisplatinum,methotrexate, cytosine arabinoside, mitomycin C, prednisone, vindesine,carbaplatinum, and vincristine. The cytotoxic agent can also be anantiviral compound which is capable of destroying proliferating cells.For a general discussion of cytotoxic agents used in chemotherapy, seeSathe, M. et al., Cancer Chemotherapeutic Agents: Handbook of ClinicalData (1978), hereby incorporated by reference.

The methods of the invention are also particularly suitable for thosepatients in need of repeated or high doses of chemotherapy. For somecancer patients, hematopoietic toxicity frequently limits theopportunity for chemotherapy dose escalation. Repeated or high dosecycles of chemotherapy may be responsible for severe stem cell depletionleading to severe long-term hematopoietic sequelea and marrowexhaustion. The methods of the present invention provide for improvedmortality and blood cell count when used in conjunction withchemotherapy.

The active agents may be administered by any suitable route, includingorally, parentally, by inhalation spray, rectally, or topically indosage unit formulations containing conventional pharmaceuticallyacceptable carriers, adjuvants, and vehicles. The term parenteral asused herein includes, subcutaneous, intravenous, intraarterial,intramuscular, intrasternal, intratendinous, intraspinal, intracranial,intrathoracic, infusion techniques, or intraperitoneally.

The active agents may be made up in a solid form (including granules,powders or suppositories) or in a liquid form (e.g., solutions,suspensions, or emulsions). The compounds of the invention may beapplied in a variety of solutions. Suitable solutions for use inaccordance with the invention are sterile, dissolve sufficient amountsof the peptide, and are not harmful for the proposed application. Inthis regard, the compounds of the present invention are very stable butare hydrolyzed by strong acids and bases. The compounds of the presentinvention are soluble in organic solvents and in aqueous solutions at pH5-8.

The active agents may be subjected to conventional pharmaceuticaloperations such as sterilization and/or may contain conventionaladjuvants, such as preservatives, stabilizers, wetting agents,emulsifiers, buffers etc.

For administration, the active agents are ordinarily combined with oneor more adjuvants appropriate for the indicated route of administration.The compounds may be admixed with lactose, sucrose, starch powder,cellulose esters of alkanoic acids, stearic acid, talc, magnesiumstearate, magnesium oxide, sodium and calcium salts of phosphoric andsulphuric acids, acacia, gelatin, sodium alginate, polyvinylpyrrolidine,and/or polyvinyl alcohol, and tableted or encapsulated for conventionaladministration. Alternatively, the compounds of this invention may bedissolved in saline, water, polyethylene glycol, propylene glycol,carboxymethyl cellulose colloidal solutions, ethanol, corn oil, peanutoil, cottonseed oil, sesame oil, tragacanth gum, and/or various buffers.Other adjuvants and modes of administration are well known in thepharmaceutical art. The carrier or diluent may include time delaymaterial, such as glyceryl monostearate or glyceryl distearate alone orwith a wax, or other materials well known in the art.

Formulations suitable for topical administration include liquid orsemi-liquid preparations suitable for penetration through the skin(e.g., liniments, lotions, ointments, creams, or pastes) and dropssuitable for administration to the eye, ear, or nose.

The dosage regimen of active agents for the methods of the invention isbased on a variety of factors, including the type of injury, the age,weight, sex, medical condition of the individual, the severity of thecondition, the route of administration, and the particular compoundemployed. Dosage levels of the order of between 0.1 ng/kg and 10 mg/kgbody weight of the active agents per body weight are useful for allmethods of use disclosed herein.

In all of these embodiments, the compounds of the invention can beadministered prior to, simultaneously with, or subsequent tochemotherapeutic exposure.

In a preferred embodiment, the active agent is administeredsubcutaneously. A suitable subcutaneous dose of the active agent ispreferably between about 0.1 ng/kg and about 10 mg/kg administered twicedaily for a time sufficient to increase white blood cell survival afterchemotherapy treatment or to mobilize hematopoietic progenitor cellsfrom bone marrow into peripheral blood. In a more preferred embodiment,the concentration of active agent is between about 100 ng/kg body weightand about 10.0 mg/kg body weight. In a most preferred embodiment, theconcentration of active agent is between about 2.5 μg/kg body weight andabout 100 μg/kg body weight. This dosage regimen maximizes thetherapeutic benefits of the subject invention while minimizing theamount of agonist needed. Such an application minimizes costs as well aspossible deleterious side effects. For example, the active agents areadministered to an oncology patient for up to 30 days prior to a courseof chemotherapy and for up to 60 days post-chemotherapy. The therapy isadministered for 1 to 6 times per day at dosages as described above. Ina further preferred embodiment, the active agent is administered onceper day.

For subcutaneous administration, the active ingredient may comprise from0.0001% to 10% w/w, e.g., from 1% to 2% by weight of the formulation,although it may comprise as much as 10% w/w, but preferably not morethan 5% w/w, and more preferably from 0.1% to 1% of the formulation.

In a preferred embodiment, subcutaneous administration of between about1 to 1000 μg/kg/day of the active agents is initiated at between oneweek before to one week after administration of a chemotherapeuticagent. In a most preferred embodiment, administration of the activeagents begins either at the time chemotherapy is initiated, or 0-10 daysafter initiation.

In another preferred embodiment of the invention, a subject undergoesrepeated cycles of treatment according to the method of this invention.Preferably, a subsequent treatment cycle commences only afteradministration of the compounds of the invention has terminated, and thesubject's blood cell counts (e.g., white blood cell count, as well asplatelet and megakaryocyte count) have returned to a therapeuticallyacceptable level (as determined by the attending veterinarian orphysician), permitting the repeated chemotherapy.

In a further aspect, the present invention provides kits for increasinghematopoietic cell survival following chemotherapy, reducing theincidence and/or severity of anemia and other side effects ofchemotherapy, and/or mobilizing hematopoietic progenitor cells from bonemarrow into peripheral blood, wherein the kits comprise an effectiveamount of the active agents for increasing hematopoietic cell survivalfollowing chemotherapy, reducing chemotherapy-induced side effects, orfor mobilizing hematopoietic progenitor cells from bone marrow intoperipheral blood, and instructions for using the amount effective ofactive agent as a therapeutic. In a preferred embodiment, the kitfurther comprises a pharmaceutically acceptable carrier, such as thoseadjuvants described above. In another preferred embodiment, the kitfurther comprises a means for delivery of the active agent to a patient.Such devices include, but are not limited to syringes, matrical ormicellar solutions, bandages, wound dressings, aerosol sprays, lipidfoams, transdermal patches, topical administrative agents, polyethyleneglycol polymers, carboxymethyl cellulose preparations, crystalloidpreparations (e.g., saline, Ringer's lactate solution,phosphate-buffered saline, etc.), viscoelastics, polyethylene glycols,and polypropylene glycols. The means for delivery may either contain theeffective amount of the active agents, or may be separate from thecompounds, which are then applied to the means for delivery at the timeof use.

In a further embodiment, the present invention provides an article ofmanufacture, comprising the pharmaceutical composition of the inventionpreloaded into a syringe or other delivery system, for home use bypatients undergoing chemotherapy.

In another aspect, the present invention provides a pharmaceuticalcomposition, comprising an amount effective of the active agents toincrease hematopoietic cell survival and/or to reduce the side effectsof chemotherapy in a chemotherapy patient, and a pharmaceuticallyacceptable carrier. In a preferred embodiment, the active agent isAII(1-7), and the effective dosage is between about 2.5 μg/kg/day and100 μg/kg/day.

In a further embodiment, the pharmaceutical composition furthercomprises an amount of cytokine effective for increasing the productionof hematopoietic cells. According to this aspect of the invention,cytokines appropriate for use include, but are not limited to,granulocyte colony stimulating factor (G-CSF),granulocyte-macrophage-CSF (GM-CSF), epidermal growth factor (EGF),interleukin 11, erythropoietin, thrombopoietin, megakaryocytedevelopment and growth factor, pixykines, stem cell factor, FLT-ligand,as well as interleukins 1, 3, 6, and 7. In a most preferred embodiment,the cytokine is granulocyte colony stimulating factor.

The methods, kits, and pharmaceutical compositions of the presentinvention, significantly enhance the utility of presently availabletreatments for clinical chemotherapeutic treatments, by providingimproved methods for increasing hematopoietic blood cell survivalfollowing chemotherapy, reducing the side effects of chemotherapy, andmobilizing hematopoietic progenitor cells from bone marrow intoperipheral blood, and also by their cytokine sparing effect, in thatsignificantly reduced amounts of cytokines are needed when administeredwith the active agents to a patient undergoing chemotherapy.

The present invention may be better understood with reference to theaccompanying example that is intended for purposes of illustration onlyand should not be construed to limit the scope of the invention, asdefined by the claims appended hereto.

Example 1 Effect of AII on White Blood Cell Mobilization and Recoveryafter 5 Fluorouracil Treatment

This study was designed to test the effect of AII on the recovery ofwhite blood cells in lymphoid organs and on the level of granulocytemacrophage precursors (CFU-GM) in the blood (ie: mobilization), spleen(mobilization), and bone marrow (recovery) after intravenousadministration of 5-fluorouracil (5FU).

Subcutaneous administration of AII (either 10 or 100 μg/kg/day) wasinitiated either two days before (−d2), the day of (d0), or two daysafter (d2) intravenous administration of 5FU. On either day 7 or 14after 5FU administration, the animals were necropsied and the spleen,thymus, peripheral blood, and bone marrow were harvested. The number ofwhite blood cells in each of the lymphoid organs, or the number ofCFU-GM present in all the organs except the thymus, were then assessed.The number of white blood cells per lymphoid organ was assessed after(1) dissociation of the tissues into a single cell suspension (thymusand spleen), (2) flushing of bone marrow from the femur, or (3) lysis ofred blood cells by a hypotonic ammonium chloride solution (blood). Analiquot of the cell suspension was diluted with 0.04% trypan blue andthe number of cells was determined by microscopic analysis using ahematocytometer. After counting, the number of cells were adjusted toallow a 1:10 dilution of cells into semi-solid medium containing fetalbovine serum, bovine serum albumin, methyl cellulose, stem cell factor,interleukin 3, interleukin 6, L-glutamine, 2 mercaptoethanol, humantransferrin and bovine insulin. On day 7 after culture initiation, thenumber of CFU-GM per well (and then per organ) was determined bymicroscopic analysis (FIGS. 1-20). These data demonstrate that AIItreatment after chemotherapy leads to significantly enhanced white bloodcell mobilization and/or recovery in all of the tissues tested.

Example 2 Effect of AII Analogues and Fragments on White Blood CellMobilization and Recovery after 5-Fluorouracil Treatment

The method was conducted as described above in Example 1, except thatmice were injected subcutaneously with 150 mg/kg body weight of 5FU, andAII peptide analogues and fragments were tested. Administration of thepeptides (see Table 3) was begun 2 days after and continued until 10days after 5FU administration, at which time the mice were euthenizedfor evaluation of bone marrow and blood GM-CFU progenitors. On days 4and 7 after 5FU administration, blood was taken under anesthesia fromthe retro-orbital sinus. On day 10, blood was taken by cardiac puncture.

The data for these experiments is shown in FIGS. 21-30, and demonstratethat all peptides tested accelerated the recovery of white blood cellsafter chemotherapy (FIGS. 21-26), increased the number of GM-CFUprogenitors in the bone marrow (FIGS. 27-28), and increased themobilization of GM-CFU progenitors from the bone marrow into theperipheral blood (FIGS. 29-30), relative to controls. The peptides wereeffective at both concentrations tested (10 μg/kg/day and 100μg/kg/day), and the efficacy generally increased with increasing lengthof treatment.

TABLE 3 Designation for Analogues/Fragments Name Abbreviation SequenceSEQ ID NO: 1GD Ala4-AII(1-7) DRVAIHP SEQ ID NO: 38 2GD Pro3-AII(1-7)DRPYIHP SEQ ID NO: 39 5GD Lys3-AII(1-7) DRKYIHP SEQ ID NO: 40 9GDNorLeu-AII(1-7) DR(nor)YIHP SEQ ID NO: 41 AII(1-7) DRVYIHP-- SEQ ID NO:4 AII DRVYIHPF SEQ ID NO. 1

Example 3 Effect of AII(1-7) on Hematopoietic Recovery After Cytoxan

In this study, female C57B1/6 mice were injected with 200 mg/kgcyclophosphamide (“cytoxan”) intravenously. Administration of AII(1-7)by subcutaneous injection was begun 2 days before or 2 days afteradministration of the antineoplastic and continued daily until necropsyfor evaluation of mature formed blood elements in the circulation andthe number of GM-CFU in the bone marrow and peripheral blood. On days 5,9, 14, 21 and 28 after cytoxan administration, blood was taken undermetofane anesthesia from the retro-orbital sinus to assess white bloodcell (WBC) and platelet number.

The data showed that AII(1-7) accelerated the recovery of WBC afterintravenous administration of cyclophosphamide when treatment withpeptides was initiated two days after the chemotherapeutic (FIG. 31 a).The increase in WBC number was observed within 9 days aftercyclophosphamide treatment. However, if AII(1-7) treatment was initiatedtwo days prior to the administration of cyclophosphamide, there was adecrease in WBC number compared with control starting on day 14 afterexposure to the chemotherapeutic (FIG. 31 b).

Administration of cyclophosphamide also significantly reduced the numberof myeloid progenitors (GM-CFU) in the bone marrow. Treatment withAII(1-7) (100 μg/kg/day) 2 days prior to treatment with cytoxan slightlyreduced the number of GM-CFU in the bone marrow of treated animals (FIG.32 a). However, initiation of AII(1-7) administration 2 days afterchemotherapy increased the number of myeloid progenitor cells in thebone marrow (FIG. 32 a). Further, administration of AII(1-7), initiatedafter cyclophosphamide treatment, increased the number of myeloidprogenitors in the peripheral blood (FIG. 32 b).

Example 4 Effect of Angiotensin Fragments and Ace Inhibitor on RecoveryAfter Chemotherapy

The next study was designed to test the effect of angiotensin peptidesand the angiotensin converting enzyme inhibitor, enalapril on recoveryof white blood cells, platelets and hemoglobin after chemotherapy, aswell as on granulocyte-macrophage colony forming units (GM-CFU) in theblood and bone marrow.

Female C67B1/6 mice (4 per group), 6-8 weeks old, were injected with 150mg/kg 5FU intravenously. Administration of the peptides (AII (100μg/kg/day), AII(1-7) (10 or 100 μg/kg/day), AII(1-5) (10 or 100μg/kg/day), and AII(1-6) (100 μg/kg/day)), by subcutaneous injection, orenalapril (30 mg/kg/day) by oral gavage, was begun 2 days afteradministration of the antineoplastic and continued daily until 28 daysafter 5FU administration, at which time the mice were euthanized forevaluation of white blood cell numbers, platelets, hemoglobin levels andthe number of GM-CFU in the bone marrow and peripheral blood. On days 7,10, 14 and 21 after 5FU administration, blood was taken under anesthesiafrom the retro-orbital sinus to assess white blood cell number, plateletnumber, and hemoglobin levels.

Retro-Orbital Bleeding of Mice

The mice were bled from the retro-orbital sinus at days 7, 10, 14 and21. The mice were anesthetized with Metofane (an inhaled anesthesia).Approximately 150-200 μl of blood were obtained from the retro-orbitalsinus with a heparinzed capillary tube. The blood was then placed in a1.7 ml microfuge tube containing 10 mM EDTA and held on ice untilfurther processing.

Hemoglobin Assay

One hundred μl of blood was pipetted into a centrifuge tube, to which900 μl of distilled water was added. The blood and water were mixed byinversion and allowed incubate at 4° C. for 20 minutes. The tube wasthen centrifuged at 12000 rpm to precipitate the cellular debri for 20to 30 minutes at room temperature. Twenty μl of the supernatant fromthis centrifugation was then added into triplicate wells of a 96 wellplate containing 180 μl of distilled water. The optical density was thenread using a microplate reader at 570 nM.

WBC and Platelet Evaluation

Twenty μl of blood was mixed with 200 μl of red blood cell (RBC) lysingsolution (0.83% NH₄Cl, 10 mM EDTA, 0.5% NaHCO₃). The mixture was thenincubated for 10 minutes at 4° C. After this incubation, the supernatantwas removed and the pellet was resuspended in 100 μl of PBS. To this,100 μl of 0.04% trypan blue was added. This mixture was vortexed and thenumber of WBC (baseline was approximately 10⁷ cells/ml) was evaluated byhematocytometer under light microscopy and the number of platelets(baseline was approximately 2.5×10⁸ platelets/ml) was evaluated byhematocytometer under phase contrast microscopy.

Evaluation of GM-CFU Progenitors in the Blood and Bone Marrow

The blood was harvested by cardiac puncture on day 10 to assessmobilization of myeloid progenitors into the peripheral blood. Thefemurs and tibia were also collected and the bone marrow was harvestedby flushing with PBS containing 2% fetal calf serum. After collection ofthe blood and bone marrow, the red blood cells were lysed with ahypotonic solution (described above), mixed with 0.04% trypan blue, andthe number of nucleated cells assessed by hematocytometer under lightmicroscopy. Aliquots of cells were then resuspended at 1×10⁵ cells/ml(bone marrow) or 1×10⁶ cells/ml (blood). One hundred μl of eachsuspension was added to 900 μl of semisolid medium containing 0.9%methyl cellulose in Iscove's MDM, 15% fetal calf serum, 1% bovine serumalbumin, 10 μg/ml bovine pancreatic insulin, 200 μg/ml humantransferrin, 10⁻⁴ M 2-mercaptoethanol, 2 mM glutamine, 10 ng/mlrecombinant murine interleukin 3, 10 ng/ml recombinant human interleukin6, 50 ng/ml recombinant murine stem cell factor and 3 units/mlerythropoietin. This mixture was then added to duplicate wells of a 24well plate. The cultures were then placed at 37° C. in a humidifiedatmosphere of 5% CO₂ in air. At day 14, the number of myeloid coloniesformed was enumerated under phase contrast microscopy.

Results

These studies were conducted to compare the effect of angiotensinfragments on hematopoietic recovery after chemotherapy. No animals werelost to analysis as a result of these therapies. The animals that diedsuccumbed to anesthesia during the bleeding procedures.

There was no difference in baseline white blood cell (WBC) numberbetween groups (8.6 to 9.0×10⁶ per ml). Baseline platelet numbers rangedfrom 2.4 to 2.6×10⁸ platelets per ml. No differences were observedbetween the groups at baseline.

These studies showed that all of the active agents tested increased thenumber of white blood cells in the peripheral blood after intravenousadministration of 5FU (FIGS. 33-35). The decrease in WBC number as aresult of administration of 5FU reached approximately 84%. The increasein WBC number was observed within 7 days after 5FU treatment (within 5days after initiation of peptide administration). The increase in WBCcontinued throughout the experimental period but varied with the activeagent. All led to the most profound effect on this parameter followed byAII(1-7) and AII(1-5). AII(1-6) and enalapril were the least effective.

Further, there was also an increase in platelets after administration ofboth AII(1-7) and AII(1-5) (FIGS. 36-38). Intravenous administration 5FUresulted in approximately a 70% decrease in platelet number that wasmaximal at day 10. Increases in platelet number occurred on days 14 and21 with all test articles increasing the concentration of platelets inthe blood.

An increase in the level of hemoglobin in the blood was observed withall active agents, except AII, on day 10 (the nadir in control animalsin this parameter). Thereafter, no further effect was observed (FIGS.39-41).

In summary, all active agents tested accelerated the recovery of whiteblood cells, platelet number, and hemoglobin level after chemotherapy.

Example 5 Phase I/II Dose Escalation Study of AII(1-7) (SEQ ID NO:4)Administered Before and After Chemotherapy in Patients with NewlyDiagnosed Breast Cancer

Delivery of optimal dosing of cytotoxic chemotherapy is often limited bymyelosuppression. Erythropoietin, filgrastim (G-CSF), sargramostim(GM-CSF), and oprelvekin (IL-11) have been the first recombinanthematopoietic growth factors to be United States Food and DrugAdministration approved to stimulate human blood production and mitigatethe toxicities of cytotoxic chemotherapy. There are a number ofadditional hematopoietic regulatory molecules that have been identifiedand are being produced in sufficient quantities to permit clinicaltesting in humans.

Data derived from pre-clinical studies demonstrated the effectiveness ofAII(1-7) (SEQ ID NO:4) in accelerating hematopoietic recovery followingchemotherapy induced myelosuppression. Additional activity on bonemarrow and peripheral blood progenitor mobilization and proliferationwas demonstrated with AII(1-7) indicating a potential for clinicalutility following myelosuppressive cancer therapies. The pharmacologiceffects appear to be multi-lineage and dose dependent.

The hematopoietic properties demonstrated in the pre-clinical studiessupport the investigation into the usefulness of AII(1-7) to decreasethe incidence and severity of complications associated withmyelosuppression secondary to cytotoxic therapy.

Based upon safety evaluation studies in animals (where the daily dosestested ranged from 10 to 1,000 μg/kg for 30 days) and the pharmacologyprofile of AII(1-7), the dose range used in humans ranged from 2.5 to100 μg/kg/day over at least 10 days. This provided for an approximate9-10 fold safety margin over the animal exposures.

Study Objectives

Primary Objectives

-   -   a) Determine the optimal biologic dose (OBD) or maximum        tolerated dose (MTD) of AII(1-7) in cancer patients before and        after treatment with cytotoxic therapy.        Secondary Objectives    -   a) Assess the hematologic profile in time to nadir, nadir, and        time to recovery (absolute neutrophil count (ANC)>500 cells/μL        and platelets>25,000/μL) in patients treated with AII(1-7) after        treatment with chemotherapy.    -   b) Assess the mobilization of CD34+ progenitor cells and colony        forming units (CFU-GM and CFU-GEMM) in peripheral blood after        AII(1-7) treatment given before and after treatment with        cytotoxic chemotherapy.    -   c) Assess the pharmacokinetic profile of AII(1-7) treatment        given before treatment with cytotoxic therapy.    -   d) Assess the incidence and days of hospitalization, febrile        neutropenia (>38.2° C. and ANC<1000 μL), and days of antibiotic        use compared to filgrastim.    -   e) Assess the influence of AII(1-7) on the chemotherapy regimen        (disease free survival (DFS) and overall survival (OS)).    -   f) Assess any synergy in hematologic response with AII(1-7) in        combination with filgrastim.        Investigational Plan

This study compared the effects of AII(1-7) (SEQ ID NO:4) in patientswith newly diagnosed breast cancer receiving doxorubicin 60 mg/m² andcyclophosphamide 600 mg/m² for at least 3 cycles of adjuvantchemotherapy following surgical tumor reduction. A filgrastim(recombinant G-CSF) (NEUPOGEN®, Amgen, Inc., Thousand Oaks, Calif.)comparator arm was used to compare safety and response variables and toassess synergy of AII(1-7) (SEQ ID NO:4) with filgrastim.

Dose Escalation Scheme

Patients who satisfied the inclusion/exclusion criteria received a oncedaily subcutaneous injection of the given AII(1-7) dose level for 7 daysfollowed by a 1 week rest period prior to any chemotherapy (cycle 0), inorder to permit evaluation of potential side effects of AII(1-7) in theabsence of toxicity due to chemotherapy. Dose escalation within anindividual patient was not be permitted. Dose escalation proceeded basedon the occurrence of dose limiting toxicity (DLT).

Post Chemotherapy Studies

Following a rest period of 7 days, a chemotherapy regimen containingdoxorubicin 60 mg/m² and cyclophosphamide 600 mg/m² was initiated.AII(1-7) was administered for at least 10 days, or until the ANC>1500 μLfor 2 days, beginning two days after chemotherapy. Up to threechemotherapy cycles followed by AII(1-7) administration were repeatedevery 21 days or as indicated by patient tolerance. Any patient thatfailed to achieve an ANC>1500/μL by day 15 (13 days of AII(1-7))received filgrastim at 5.0 μg/kg/day until the ANC>1500/μL for 2 days.Dosing began with the lowest dose of AII(1-7). In combination with eachdosing group of AII(1-7), one additional patient received filgrastim 5.0μg/kg/day beginning two days after chemotherapy and continuing for atleast 10 days or until the ANC>1500/μL for 2 days. These patients wereused for comparison with the AII(1-7) treated patients. Any patient inthe AII(1-7) dosing arm that experienced an episode of febrileneutropenia following chemotherapy or failed to achieve an ANC>1500/μLduring the first cycle received filgrastim at 5.0 μg/kg/day incombination with AII(1-7) for the remaining chemotherapy cycles. Theremaining cycles for that patient were treated with filgrastim offprotocol as determined by the Investigator. Patients received supportivetreatment consistent with the standard of care as determined by theInvestigator.

Endpoints

The primary safety endpoints were the incidence and grade of toxicityexperienced by each dose group (DLT), MTD or OBD, changes inbiochemistry, hematology, urinalysis, physical findings, and adverseevents. Secondary safety endpoints were DFS and OS.

The preliminary efficacy endpoints were time to nadir (i.e.: the lowpoint), nadir, and hematologic recovery (ANC>500/μL andplatelets>25,000/μL), mobilization of CD34+ progenitor cells, CFU-GM andGEMM after AII(1-7) (SEQ ID NO:4) treatment given before and aftercytotoxic chemotherapy, and incidence and number of days of febrileneutropenia (>38.2° C.; ANC<1000 μL), hospitalization, infection, andantibiotic use.

Treatments

AII(1-7), filgrastim or both were self-administered following adequatepatient training. AII(1-7) was administered once daily with asubcutaneous needle into a site located in the abdomen or thigh everymorning.

Efficacy and Safety Variables

Hematology

Hematology assessment included red blood cell count (RBC), hemoglobin(Hgb), hematocrit (Hct), mean corpuscular volume (MCV), mean corpuscularhemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC),white blood cell count (WBC) including differential, reticulocyte count,and platelet count.

Coagulation

A coagulation panel was obtained for prothrombin time (PT) and activatedpartial thromboplastin time (PTT).

Adverse Event

An adverse event (AE) was considered as any unfavorable or unintendedchange in structure, function, signs, or symptoms temporally associatedwith the use of a medicinal product experienced by a person administereda pharmaceutical product, whether or not a causal relationship with theproduct was established. Clinically significant laboratory abnormalitieswere considered AEs if deemed appropriate by the Investigator. Worseningof a pre-existing condition was also considered an AE, as was thediscovery of an abnormal finding during physical exam that was notincluded in the medical history.

Appropriateness of Measurements

The occurrence of febrile neutropenia was associated with significantmorbidity and mortality in patients following myelosuppressivechemotherapy.

Primary Efficacy Variables

CD34+ assays

Peripheral blood was collected to conduct CD 34+ cell mobilizationassays. Blood samples were obtained with a draw volume of 2 mL bloodcollection tubes.

Febrile Neutropenia

Patients were instructed to notify the Investigator of any oraltemperature ≧38.2° C. Patients had a CBC obtained anytime they presentwith fever. If the ANC was <1000 μL in conjunction with an oraltemperature ≧38.2° C., two blood cultures for aerobic/anaerobic bacteriawere obtained, drawn 15 minutes apart.

Drug Concentration Measurements

Pharmacokinetics samples for the measurement of AII(1-7) and AII werecollected and centrifuged. The specimen was decanted into a plastictransfer vial and stored at −20° C. Blood samples were obtained with adraw volume of 5 mL.

Results:

Administration of AII(1-7) resulted in an increase in multiplehematopoietic lineages and mobilization of hematopoietic progenitorsinto the peripheral blood. A dose dependent increase in the level ofnadir in the number of white blood cells and absolute neutrophil countand time to these nadirs was observed. This is consistent with an effecton the compound on myeloid recovery after chemotherapy. At the lowerdoses, administration of filgrastim was required on Day 15 to restoreacceptable levels of WBC prior to the next chemotherapy cycle. However,only one to two doses were required to substantially increase WBC andANC suggesting a priming of the bone marrow cells for response todifferentiating colony stimulating factors and a cytokine sparing effectof AII(1-7).

An additional benefit of administration of AII(1-7) was the ability ofall patients to maintain on cycle, full intensity chemotherapy. It isexpected that, after the first cycle of chemotherapy, the full dose ofchemotherapeutic drug would not be administered to the patient at thetime that would be optimal for cancer therapy, due to a dose-limitingtoxicity that requires resolution. However, AII(1-7) administrationpermitted the patients to maintain full intensity chemotherapy on cycle.

Further, administration of AII(1-7) resulted in a dose-dependentincrease in platelets. At the lowest dose, the nadir in platelet numberoccurred on day 12 and platelet number recovered thereafter. At 50μg/kg/day of AII(1-7), only day 12 showed any change in platelet number.At the next higher dose, no decrease in platelet number occurred. Infact, an early increase relative to baseline was observed. In contrast,patients that received filgrastim had a time dependent decrease inplatelet number that was more pronounced in subsequent cycles ofchemotherapy.

Administration of AII(1-7) also affected the correction of anemiafollowing administration of chemotherapeutic drugs. It was expected thatadministration of the chemotherapeutic drug would reduce the bloodhemoglobin levels, that this reduction would not be corrected within thechemotherapy cycle and that the anemia would get progressively worse.This was observed after administration of filgrastim in these patients.After administration of the lowest dose of AII(1-7), a reduction inhemoglobin was observed. Contrary to that expected after administrationof the chemotherapeutic drug in the absence of an adjuvant, thehemoglobin level returned to baseline levels by the next cycle. Atsubsequent dose increases of AII(1-7), slight to no anemia was observed,but at all doses, restoration of hemoglobin prior to the next cycle wasobserved.

To date, 14 patients have been exposed to AII(1-7) at 4 dosages (2.5μg/kg/d, 10 μg/kg/d, 50 μg/kg/d, 75 μg/kg/d, and 100 μg/kg/d).Cumulative doses of >1500 μg/kg have been reached. No acute affect onblood pressure following administration has been observed in patientswith or without a history of hypertension. No dose-limiting toxicitieshave been observed with AII(1-7) and all study patients have received100% dose intensive chemotherapy to date. Anemia correction with eachcycle has been observed with doses as low at 2.5 μg/kg. No drug relatedserious adverse events have been observed. No cycle delays due toneutropenia have occurred, however, patients treated at 2.5 and 10 μg/kghave needed 1-2 doses of filgrastim at day 15 to treat grade 4neutropenia as directed by the protocol. Of note is that following 10-12days of AII(1-7), as little as 1 dose of filgrastim normalizes theneutrophil count indicating a possible synergy between filgrastim andAII(1-7).

AII(1-7) reduced the frequency of grade 2-4 thrombocytopenia, grade 2-4anemia, and grade 3-4 lymphopenia compared to filgrastim. Filgrastimpatients experienced a lower frequency of grade 3-4 neutropenia comparedto AII(1-7), however, the frequency of grade 3-4 leukopenia was similarin both groups. The most prominent hematologic effect with AII(1-7) wasthe prevention of thrombocytopenia.

Toxicity Filgrastim 2.5 μg/kg 10 μg/kg 50 μg/kg 75 μg/kg 100 μg/kg Hgb<10 gm/dl 60% 66% 33%  0% 0% 0% Platelet <80K/μl 60%  0%  0%  0% 0% 0%Lymph <500/μl 80% 66% 33% 33% 0% 0% ANC <1000/μl 40% 100%  100%  100% 100%  100%  WBC <2000/μl 60% 66% 66% 66% 100%  33%  Hgb = hemoglobinLymph = lymphocyte ANC = Absolute neutrophil count WBC = white bloodcells

Additionally, AII(1-7) reduced the frequency of stomatitis by 30% ofthat observed with filgrastim treatment, as well as decreasing thefrequency of a number of other common side effects of chemotherapy, suchas headache, muscle pain, and alopecia, relative to both historicalnumbers and filgrastim controls.

AII(1-7) Filgratim Treatment Group Historic (n = 15) (n = 5) Nausea 90%93% 100% Fatigue 93% 80% Anemia 22%  7% 60% Vomiting 80% 60% Headache26% 60% Stomatitis 88% 40% 60% Myalgia/Muscle- 53% 60% skeletal painAlopecia 77% 46% 40%

In summary, the data demonstrate the following:

-   -   AII(1-7) is safe without observed dose limiting toxicities.    -   Doses of AII(1-7) greater than 10 μg/kg/day appear to be active;        the optimal dosage range appears to be 50-75 μg/kg/day.    -   No over-production of formed blood elements occurs before or        after chemotherapy.    -   AII(1-7) reduces the frequency of gradable anemia, lymphopenia,        and thrombocytopenia compared to filgrastim treated patients.    -   Neutrophil nadirs are not affected by AII(1-7), but late        recovery is enhanced compared to filgrastim.    -   AII(1-7) improves the recovery towards baseline in all formed        blood elements and minimizes pre-cycle progressive pancytopenia        associated with myelosuppressive chemotherapy.

It is to be understood that the invention is not to be limited to theexact details of operation, or to the exact compounds, compositions,methods, procedures or embodiments shown and described, as obviousmodifications and equivalents will be apparent to one skilled in theart, and the invention is therefore to be limited only by the full scopeof the appended claims.

1. An improved method for multiple cycle chemotherapy in a humanpatient, wherein the improvement comprises administering to the humanchemotherapy patient an amount effective of a polypeptide consisting ofat least 5 amino acids of SEQ ID NO:4 to permit treatment of the humanchemotherapy patient with at least the same chemotherapy dosage on asecond or further chemotherapy cycle as on the first chemotherapy cycle.2. The improved method of claim 1, wherein the polypeptide consists ofthe amino acid sequence of SEQ ID NO:4.
 3. The improved method of claim2, wherein the polypeptide is administered at a dosage of between 2.5μg/kg/day and about 100 μg/kg/day.
 4. The improved method of claim 2,wherein the polypeptide is administered at a dosage of between 10.0μg/kg/day and about 100 μg/kg/day.
 5. The improved method of claim 2wherein the polypeptide is administered parenterally.
 6. The improvedmethod of claim 2 wherein the polypeptide is administered subcutaneouslyor intravenously.
 7. The improved method of claim 2 whereinadministration of the polypeptide is initiated either at the timechemotherapy is initiated, or subsequent to initiation of chemotherapy.8. The improved method of claim 2 wherein the human chemotherapy patientis treated with one or both of doxorubicin and cyclophosphamide.
 9. Theimproved method of claim 2 wherein the human chemotherapy patient istreated for 3 chemotherapy cycles.
 10. The improved method of claim 2wherein the method further comprises treating the human chemotherapypatient with a cytokine selected from the group consisting ofgranulocyte colony stimulating factor, granulocyte-macrophage-CSF,epidermal growth factor, interleukin 11, thrombopoietin, megakaryocytedevelopment and growth factor, pixykines, stem cell factor, FLT-ligand,and interleukins 1, 3, 6, and
 7. 11. The improved method of claim 1,wherein the polypeptide is administered at a dosage of between 2.5μg/kg/day and about 100 μg/kg/day.
 12. The improved method of claim 1,wherein the polypeptide is administered at a dosage of between 10.0μg/kg/day and about 100 μg/kg/day.
 13. The improved method of claim 1wherein the polypeptide is administered parenterally.
 14. The improvedmethod of claim 1 wherein the polypeptide is administered subcutaneouslyor intravenously.
 15. The improved method of claim 1 whereinadministration of the polypeptide is initiated either at the timechemotherapy is initiated, or subsequent to initiation of chemotherapy.16. The improved method of claim 1 wherein the human chemotherapypatient is treated with one or both of doxorubicin and cyclophosphamide.17. The improved method of claim 1 wherein the human chemotherapypatient is treated for 3 chemotherapy cycles.
 18. The improved method ofclaim 1 wherein the method further comprises treating the humanchemotherapy patient with a cytokine selected from the group consistingof granulocyte colony stimulating factor, granulocyte-macrophage-CSF,epidermal growth factor, interleukin 11, thrombopoietin, megakaryocytedevelopment and growth factor, pixykines, stem cell factor, FLT-ligand,and interleukins 1, 3, 6, and 7.